private IEnumerable <ICandidate> CollectCandidatesAtTrie(string prefix, ArrayTrie trie)
{
var candidates = new List <ICandidate>();
var trieQueue = new Queue <Tuple <string, ArrayTrie> >();
trieQueue.Enqueue(new Tuple <string, ArrayTrie>(prefix, trie));
while (trieQueue.Count != 0)
{
var nextTrieTuple = trieQueue.Dequeue();
var nextPrefix = nextTrieTuple.Item1;
var nextTrie = nextTrieTuple.Item2;
for (int i = 0; i < nextTrie._subTries.Length; i++)
{
ArrayTrie subTrie = nextTrie._subTries[i];
if (subTrie != null)
{
char character = MapIntToChar(i);
if (subTrie._isTerminatedWord)
{
candidates.Add(new Candidate(nextPrefix + character, subTrie._wordOccurenceCount));
}
trieQueue.Enqueue(new Tuple <string, ArrayTrie>(nextPrefix + character, subTrie));
}
}
}
return(candidates);
}
private ArrayTrie FindLastSubTrieIfExists(string word)
{
ArrayTrie currentTrie = this;
foreach (var c in word)
{
int index = MapCharToInt(c);
if (currentTrie._subTries[index] != null)
{
currentTrie = currentTrie._subTries[index];
}
else
{
return(null);
}
}
return(currentTrie);
}
public void TrainTrie(IEnumerable <string> words)
{
foreach (var word in words)
{
ArrayTrie currentTrie = this;
foreach (char c in word)
{
int index = MapCharToInt(c);
if (currentTrie._subTries[index] == null)
{
currentTrie._subTries[index] = new ArrayTrie();
}
currentTrie = currentTrie._subTries[index];
}
currentTrie._isTerminatedWord = true;
currentTrie._wordOccurenceCount++;
}
}
private string ToString(int level)
{
if (_subTries == null)
{
return("");
}
level++;
var sb = new StringBuilder();
for (int i = 0; i < _subTries.Length; i++)
{
ArrayTrie subTrie = _subTries[i];
if (subTrie != null)
{
char c = MapIntToChar(i);
sb.Append("{ " + level + " " + c + " : " + _subTries[c].ToString(level) + "}");
}
}
return(sb.ToString());
}
